1. Field of the Invention
The present invention relates to an image processing apparatus and an image processing method.
2. Description of the Related Art
When visually tracking a moving object (e.g. telop) on an impulse type display having quick response speed, the background of the previous frame image (background which is no longer displayed (especially the edge portion)) may be seen as an after image, which is characteristic of the human visual sense. Sometimes multiple images of a background are seen, which exhibits an artificial sensation. This phenomena tends to occur on an SED (Surface-condition Electron-emitter Display), FED (Field Emission Display) and on an organic EL display, for example.
FIG. 15 shows two frame images which are continuous in time. The area enclosed by the dotted line indicates a field of view of a viewer. As FIG. 15 shows, the background around a telop (“ABC” in FIG. 15) in frame image 1 is seen by the viewer as an after image also in frame image 2. This is because human eyes have the characteristic of “tracking a moving object”, where “instantaneous light emission persists in human vision (that is, if the display apparatus is an impulse type, the previous frame image continues to be seen)”. Particularly in the case of viewing an image displayed on a large screen display apparatus at a distance close to the screen, interference by an after image increases, since the moving distance of the field of view, when the viewer is tracking a moving object, increases.
An available prior art determines whether a pixel in an edge portion (edge pixel) is a pixel in a target area (area the viewer is focusing on) or not, based on the density of peripheral edge pixels (edge density), and decreases high frequency components in an area of which edge density is high (Japanese Patent Application Laid-Open No. 2001-238209).
However an area of such a pattern as “leaves” around which a moving object does not exist could be a target area, but the edge density in such an area is high. A motion area, where an image is moving, could become a target area, but if this area is an area for a telop, the edge density in this area also is high. If the technology disclosed in Japanese Patent Application Laid-Open No. 2001-238209 is used in these cases, such a target area blurs.